import time

from django.utils.deprecation import MiddlewareMixin

MAX_REQUEST_PER_SECOND=2 #每秒访问次数


class RequestBlockingMiddleware(MiddlewareMixin):
    def process_request(self,request):
        print('hello')
        now=time.time()
        request_queue = request.session.get('request_queue',[])
        if len(request_queue) < MAX_REQUEST_PER_SECOND:
          request_queue.append(now)
          request.session['request_queue']=request_queue
        else:
          time0=request_queue[0]
          if (now-time0)<1:
            time.sleep(5)

          request_queue.append(time.time())
          request.session['request_queue']=request_queue[1:]